CurtisMcArthur

Ok, I'm brand new to this forum because up until today I didn't own an Audi. That's right, I bought an automatic '01 2.8 A4 today and while driving it home a rumble appeared from nowhere. I purchased the car on eBay, flew up to D.C. this morning, picked it up, and drove it back to Knoxville, TN. I literally just got back. The car ran fine the entire way until about 20 miles out when i pulled over the fill up the tank. I noticed the growl/rumble when i accelerated from the stop sign at the exit. It's a different pitch depending on the gear its in, and when i first step on the gas or let off the gas it makes a kind of gargling sound. Anyways, I was so close to home that i decided to just drive it slow the remaining 20 miles, which seems to have played out ok, but I guess i wont really know till the shop takes a look at it. Im definitely no expert, but the only thing that comes to mind is a faulty or loose O2 sensor.....i've heard similar grows when my Lexus had the O2 sensor removed and i hit the gas. However, while the car will still get up to speed, it has definitely lost power. The sound is extremely loud...imagine the most obnoxiously loud ricer's exhaust x10! I'm going to have nightmares about it after this is over. Anyways, just thought I'd get your all's opinions, tranny, engine? I hope this guy didnt intentionally sell me a lemon, but it's sure looking that way. btw, the car has 114,000 miles on it. Lemme know what ya think. thanks!

Curtis

CurtisMcArthur

so i'm doing some research and it sounds like i might have an exhaust leak, something about clamps wearing out and going bad......and possibly a blown catalytic converter? maybe the flex pipe needs replacing?

Allroady DungBeetle

Most likely one or both flex joints are gone. Common and typical on older cars.

CurtisMcArthur

hey thanks, just got down on my back w a flashlight and sure enough, both flex joints need to be replaced. do i need to order them or if i go to the muffler shop will they have them in stock?

CurtisMcArthur

here's a pic i took this morning, looks pretty conclusive to me.
do they just break off after so long or do you think i hit something to break them? still trying to find a muffler shop open on sunday, dont know if its gonna happen......

Allroady DungBeetle

Wow, those are gone. Nobody will be open today. And you'll probably have to order them but maybe not depending how well stocked a shop go to.

The down-pipes will have to come off the manifolds and the joints welded on.... I have done them *in* the car, but 99% of shops will want to take it apart as it is a lot easier to do that way. Also if I was to warranty my work I'd pull them off and weld it on the bench to get a better weld.

You may also find some shops will tell you you have to replace the pipes, joints and cats as they are one piece.... find a custom shop and they can weld in a new flex joint.

Also look inside the cats and make sure the "cat guts" (LOL) are not loose in there or cracked - if they are now is the time to replace the whole thing.

Doug

Allroady DungBeetle

Also your rear trans output seal is leaking.

MartinH

I had them replaced in-situ on my 96 2.8 so it is possible, but the weld on the top of the joint is not the best!

jaimesonlee

Nice observation on that output seal!

jimrobertson

Someone is paying attention.Never would have known.